1. Technical Field
The present invention relates to a haptic device and a display having the same.
2. Background Art
Mobile devices, which are currently in the markets in a variety of forms, including mobile phones, GPS navigators, DIDs (digital information displays) and tablet computers, are basically equipped with a touch interface. One of the methods standing out recently for augmenting user experience by linking with the touch interface is the haptic technology. When a user interacts with a digital object, the haptic technology links the user with the GUI to provide a more realistic user interface by providing a feedback with visual and tactile senses fused therein.
The most common conventional method for providing tactile senses is a motor method, which has been variously utilized in mobile devices, owing to the small size, fast reaction speed, low power and ease of tactile power control. However, when the tactile senses are provided using the motor method, it is difficult to dispose the tactile module due to its size, and the mobile device has to be inevitably thick. Particularly, since vibrations are delivered to the entire device when the conventional motor method is used, the tactile senses are felt by the hand holding the device, rather than by the touching hand, making it difficult to apply the motor method to non-handheld devices such as GPS navigators, DIDs and monitors.
Appeared to overcome this shortcoming is a film-type haptic module technology that can be installed over a display panel. The film-type haptic module mainly utilizes deformation of an electroactive polymer material or utilizes an electrostatic force. In the case of using an electroactive polymer material, it is possible to realize a film-type haptic module that consumes less electric power and has a fast reaction speed. However, since it is difficult to generate a sufficient force with the deformation of the polymer material only, an additional device (i.e., mass) having a certain weight is often used. In the end, the physical shape of the electroactive polymer material is deformed using electric energy, and the repeated deformation of the physical shape cause a periodic motion of the additional device. Then, the change in acceleration generated by the motion of the additional device delivers tactile senses to the user. Therefore, in this case, the electroactive polymer material and the additional device are required in order to generate a sufficient output.
A conventional method using the electrostatic force is disclosed in Korean Patent Application No. 2011-7018443, in which same or different electric charges are electrified, respectively, to 2 substrates, each having a conductive material coated thereon, while the 2 substrates are arranged to face opposite to each other, and tactile senses are generated by instantaneous attractive and repulsive forces caused by an electrostatic force generated between the 2 substrates. An actuator device constituted with these 2 substrates is configured independently above or below a touch panel. In an actual application, an insulating layer inserted between the substrates is additionally required to prevent electric conduction.
Another conventional method using electrostatic force uses electrostatic forces generated between a substrate having a conductive material coated thereon and a hand of the user. An advantage of this method is that there is no mechanical motion when the tactile senses are outputted. Nevertheless, since the electrostatic force generated between the substrate and the hand of the user is too small, the tactile senses are hardly delivered by simply having the hand of the user touch the substrate, except some frictional senses when the hand moves on the substrate.
The above-described conventional technologies are structured to have the entire device vibrated, to have the entire substrate, in which two sheets of electrodes are constituted as one actuator, vibrated, or to have tactile senses delivered when the hand of the user moves on the substrate, without mechanical vibrations. In the first case, the tactile senses are hardly provided unless it is a handheld device. In the second case, the device become thicker due to the space between the two sheets of electrodes, and the actuator itself may not be very durable due to foreign objects such as dust. In the third case, there are limited situations when the tactile senses can be provided. That is, the tactile senses may be delivered only when the hand is moving on the substrate.
The related art is described in U.S. Pat. No. 8,797,295.